2000 INTERPRETIVE SUMMARY NEW YORK CITIZENS STATEWIDE LAKE ASSESSMENT PROGRAM (CSLAP) WEST CAROGA LAKE Scott A. Kishbaugh Betsy R. Hohenstein NYS Department of Environmental Conservation Division of Water, Lake Services Section September 2001 Page 2 BACKGROUND AND ACKNOWLEDGMENT The Citizens Statewide Lake Assessment Program (CSLAP) is a volunteer lake monitoring program conducted by the NYS Department of Environmental Conservation and the NYS Federation of Lake Associations. Founded in 1986 with 25 pilot lakes, the program now involves more than 150 lakes, ponds, and reservoirs and 1000 volunteers from eastern Long Island to the Northern Adirondacks to the western-most lake in New York, including several Finger Lakes, Lake Ontario, and lakes with state parks. In this program, lay volunteers trained by the NYSDEC collect water samples, observations, and perception data every other week in a fifteen-week interval between May and October. Water samples are analyzed by the NYS Department of Health. Analytical results are interpreted by the NYSDEC and utilized for a variety of purposes by the State of New York, local governments, researchers, and, most importantly, participating lake associations. This report summarizes the 2000 sampling results for West Caroga Lake. West Caroga Lake is a 313 acre, class B lake found in the Town of Caroga in Fulton County, in the southern Adirondack area of New York State. West Caroga Lake has been sampled as part of CSLAP since 1997. The following volunteers have participated in CSLAP, and deserve most of the credit for the success of this program at West Caroga Lake: Thomas Gilbert, Linda Gilbert and Ronald Soviero. In addition, the authors wish to acknowledge the following individuals, without whom this project and report would never have been completed: From the Department of Environmental Conservation, N.G. Kaul, Sal Pagano, Dan Barolo, Italo Carcich, and Phil DeGaetano, for supporting CSLAP for the past fifteen years; Jay Bloomfield and James Sutherland, for their work in developing and implementing the program; the technical staff from the Lake Services Section, for continued technical review of program design; and Becky Bird for assistance in copying and distributing this report. From the Federation of Lake Associations, Anne Saltman, John Miller, Nancy Mueller, Dr. John Colgan and the Board of Directors, for their continued strong support of CSLAP. The New York State Department of Health, particularly Jean White, provided laboratory materials and all analytical services, reviewed the raw data, and implemented the quality assurance/quality control program. Finally, but most importantly, the authors would like to thank the more than 1000 volunteers who have made CSLAP a model for lay monitoring programs throughout the country and the recipient of a national environmental achievement award. Their time and effort have served to greatly expand the efforts of the state and the public to protect and enhance the magnificent water resources of New York State. Page 3 WEST CAROGA LAKE FINDINGS AND EXECUTIVE SUMMARY West Caroga Lake has been sampled as part of the New York Citizens Statewide Lake Assessment Program since 1997. Water quality conditions and public perception of the lake each year have been evaluated within annual reports issued after each sampling season. Historical water quality summaries of the CSLAP data have also been undertaken within each annual report. This report attempts to summarize both the 2000 CSLAP data and an historical comparison of the data collected within the 2000 sampling season and data collected at West Caroga Lake since 1997. Due to a delay in receiving phosphorus data from the analytical laboratory, and the resulting expediency required to get this information into the hands of the sampling volunteers, the summary report for West Caroga Lake and other CSLAP lakes was unexpectedly delayed. However, the data presented here represent a complete dataset, which would not have otherwise been available if this report were issued in a more timely fashion. The majority of the short- and long-term analyses of the water quality conditions in West Caroga Lake are summarized in Table 2, divided into assessments of eutrophication indicators, other water quality indicators, and lake perception indicators. These assessments are somewhat limited by the lack of a substantial water quality database for 2000, since only two samples were collected. These limited data suggest that water quality conditions in West Caroga Lake continue to be indicative of a moderately unproductive lake. Water clarity readings in 2000 were substantially lower than in previous sampling seasons, but this was not coincident with an increase in algae growth or nutrient concentrations. This suggests that the drop in water clarity may not have been related to a “systemic” change in the lake, but may have been due to other contributors to turbidity, such as suspended sediment (dissolved organic carbon levels, as measured by water color, were higher, although it is not likely that this was the only factor contributing to the drop in transparency). Overall recreational conditions continue to be rated very favorably, due to the continued high water clarity and relatively low levels of invasive weed growth (perhaps due to the success of the active plant management activities on the lake). Most of the other water quality indicators do not appear to have changed significantly since CSLAP sampling began in 1997. With the exception of an occasionally low pH reading (which may be a laboratory arefact inherent in the lab measurement of pH), none of the other applicable water quality standards (including water clarity) were violated during these CSLAP sampling sessions. The 1996 NYSDEC Priority Waterbody Listing (PWL) for the Mohawk Basin does not include West Caroga Lake. The CSLAP dataset suggest that no listings may not longer be warranted. The next formal review of the PWL Listings for this basin will likely take place in 2003. In summary, consistent with relatively unproductive lake conditions, recreational assessments of West Caroga Lake continue to be mostly favorable and supportive of most recreational uses (at least those assessable through CSLAP). While water clarity was slightly lower in 2000, it does not appear that this has (at least yet) adversely influenced recreational assessments of West Caroga Lake. Page 4 I. INTRODUCTION: CSLAP DATA AND YOUR LAKE Lakes are dynamic and complex ecosystems. They contain a variety of aquatic plants and animals that interact and live with each other in their aquatic setting. As water quality changes, so too will the plants and animals that live there and these changes in the food web also may additionally affect water quality. Water quality monitoring provides a window into the numerous and complex interactions of lakes. Even the most extensive and expensive monitoring program cannot completely assess a lake’s water quality. However, by looking at some basic chemical, physical, and biological properties, it is possible to gain a greater understanding of the general condition of lakes. CSLAP monitoring is a basic step in overall water quality monitoring. Understanding Trophic States All lakes and ponds undergo eutrophication, an aging process, which involves stages of succession in biological productivity and water quality (see Figure 1). Limnologists (scientists who study fresh water systems) divide these stages into trophic states. Each trophic state can represent a wide range of biological, physical, and chemical characteristics and any lake may “naturally” be categorized within any of these trophic states. In general, the increase in productivity and decrease in clarity corresponds with an enrichment of nutrients, plant and animal life. Lakes with low biological productivity and high clarity are considered oligotrophic. Highly productive lakes with low clarity are considered eutrophic. Lakes that are mesotrophic have intermediate or moderate productivity and clarity. Eutrophication is a natural Figure 1. Trophic States process, and is not necessarily indicative of man- made pollution. In fact, some lakes are thought to be “naturally” productive. It is important to understand that trophic classifications are not interchangeable with assessments of water quality. One person's opinion of degradation may be viewed by others as harmless or even beneficial. For example, a eutrophic lake may support an excellent warm-water fishery because it is nutrient rich, but a swimmer may describe that same lake as polluted. A lake’s trophic state is still important because it provides lake managers with a reference point to view changes in a lake’s water quality and begin to understand how these changes may cause use impairments (threaten the use of a lake or swimming, drinking water or fishing). When human activities accelerate lake eutrophication, it is referred to as cultural eutrophication. Cultural eutrophication may result from shoreline erosion, agricultural and urban runoff, wastewater discharges or septic seepage, and other nonpoint source pollution sources. These can greatly accelerate the natural aging process of lakes, cause succession changes in the plant and animal life within the lake, shoreline and surrounding watershed, and impair the water quality and value of a lake. They may ultimately extend aquatic plants and emergent vegetation throughout the lake, resulting in the transformation of the lake into a marsh, prairie, and forest. The extent of cultural eutrophication,